Formwork – 5 Types of Formwork | Purpose of Formwork | Requirements and Advantages of Good Formwork

What is Formwork in Construction?

Formwork is a mould utilized in construction to give a preferred structural shape through pouring concrete into the mould. Formwork, in a nutshell, is a mould used to cast concrete members of numerous forms and sizes. There are numerous styles of Formwork in the market. Sometimes formwork is also called shuttering on site.

Types of Formworks in Construction

1. Steel Formwork
2. Aluminium Formwork
3. Timber Formwork
4. Plywood Formwork
5. Fabric Formwork
6. Plastic Formwork

Steel Formwork

Steel Formwork is popular today since it has a long-life span and allows for greater repetition. They are mostly made of steel plates and angles to make the desired shape in which the concrete is to be casted. Steel Panel parts are frequently linked together with appropriate clamps, nuts, and bolts. Steel Panels might also be manufactured in any conventional shape or dimension. This type of Formwork is frequently used for round and curving constructions, as well as when casting ceilings, etc.

Advantages of using Steel Formwork

1. Steel Panels are also quickly and easily placed and disassembled.
2. Steel panels are a lot of robust, stronger, and have an extended life span.
3. Steel panels don’t absorb wetness or water from concrete.
4. it’s cost-efficient if there’s plenty of building going on.
5. the quality of the concrete surface created by steel formworks is smooth, and no additional treatment is required.
6. This Formwork doesn’t shrink or warp.

Also Read: Mivan Technology

Aluminium Formwork

Aluminium formwork is similar to Steel Formwork. Because of the low density of aluminium, this form of formwork is lighter than metal formwork. If an extensive wide variety of repetitions are executed in Construction, this fashion of formwork is fee effective.

Advantages of using Aluminium Formwork

1. Aluminium formwork is reusable as much as 250 times.
2. Aluminium Formwork quickens construction and saves time and labour.
3. If a sizeable range of symmetrical systems is to be created, it’s miles cost-effective.
4. It produces a greater polished and clean floor finish.

Timber Formwork

Timber formwork is one of the most generally utilised withinside the constructing business, and it is made on-site from wood. It is straightforward to make, but time-eating for larger buildings. The durability of plywood face is limited. Timber is lightweight, smooth to install, and remove. Timber shuttering is the maximum adaptable kind of shuttering, for the reason that it is able to be utilised for any form or size.

Advantages of using Timber Formwork

1. Timber shuttering is cost-effective for small tasks.
2. Timber shuttering is easy to construct in any shape, size, or height.
3. Timber shuttering is viable to construct it out of domestically to be had wood.
4. Timber shuttering can be effectively fashioned and sized to any shape or size.
5. Timber shuttering is lighter in weight than metallic or aluminium shuttering.
6. Because timber has a high heat resistance, it reduces concrete degradation in cold climates.
7. Because the development technique for this shape of Formwork is simple, it does now no longer necessitate the usage of specialized workers.

Also Read: Defects in Timber | Causes of Timber defects

Plywood Formwork 

Plywood is another type of formwork that is a man-made wood substance that is available in numerous thicknesses and sizes and is utilized in formwork for concrete members. It is long-lasting, lightweight, and sturdy. Plywood is a famous fabric for decking, shape linings, and sheathing in shuttering.

Plywood for concrete formwork is BWP (Boiling waterproof) grade plywood that has been preservative-handled and is right to be used in shuttering and formwork. Plywood formwork is specifically valued powerful on account that it could be used again, relying at the care used all through setup and removal.

Advantages of using Plywood Formwork

1. Plywood is a robust, long-lasting, and light-weight material.
2. Plywood is simply to cut into an appropriate size.
3. Plywood hurries up and simplifies formwork.
4. Plywood creates an easy end at the concrete surface.

Fabric Formwork

In Fabric formwork geotextiles are used as the formwork. Structural membranes which are geotextile in this case are used as the face material of concrete mould. This formwork is quite different than other formwork, some of the characteristics of this formwork are: –

• fabric formwork is pliable enough to form beams, columns, and walls, among alternative things.
• These systems can be used for both precast and cast-in-place concrete construction.
• The tension from the wet concrete is taken by the geotextile in the form work which reduces the requirement of the addition formwork material resulting in cost saving.
• fabric forms surpass traditional formwork in terms of longevity, surface polish, and subject area aesthetics.
• beneath the pressure of wet concrete, the fabric mould develops the required shape.
• Geotextile textiles are porous enough to enable excess water and air bubbles in the concrete combine to flee through the formwork, leading to a stronger and additional water-resistant concrete.
• fabric forms aid within the creation of difficult shapes by victimization less concrete and reinforcement.

Advantages of using Fabric Formwork

1. it’s watertight.
2. It is far lighter than the other formwork material.
3. material formwork could also be used to produce any sophisticated shape.
4. it’s cost-effective.
5. once the concrete has hardened, it is straightforward to remove.
6. it’s no impact on the characteristics of the concrete.

Plastic Formwork

Plastic is another sort of formwork material this is utilised for tiny concrete buildings or problematic structural components. It is low in weight and lasts for a long time. Glass reinforced plastics (GRP) and vacuum formed plastics are hired for complicated concrete constructions.

Advantages of using Plastic formwork

1. Formwork for complicated shaped constructions could also be simply created.
2. Plastic is lightweight and easy to figure with.
3. High-quality plastic is very reusable.
4. broken plastic sheets may be recycled and reused to form new sheets.
5. Water-resistance is excellent.

What is the purpose of formwork?

The main purpose of formwork is to safely support the reinforced concrete until it reaches the required strength and give shape to the concrete poured in it as per the drawing’s requirement.

Why is formwork needed for placing concrete?

Formwork is needed for concrete to solidify in the appropriate form whereas additionally increasing strength and durability.

What are the requirements of good formwork?

The requirements of good formwork are: –

1. It should be rigidly constructed and effectively propped and maintained with the purpose to hold its shape without undue distortion.
2. It should be robust enough to maintain a huge range of dead and live loads. For example, self-weight, reinforcing weight, moist concrete weight, worker loads, and any extra loads throughout and after concrete casting.
3. The formwork should be designed in one of these manners so that it is able to be evacuated in the right order without shaking or harming the concrete.
4. The formwork joints should be tight enough to keep away from cement grout leaking.
5. The formwork material should be affordable, readily available, and used several times.
6. It should be light and easy to handle.
7. The formwork surface should be flat and smooth, and it should be fitly adjusted to the needed line and level.
8. The formwork after the work should be easily removable.
9. The formwork material shouldn’t bend or get crooked within the presence of sunlight, rain, or water throughout the concreting process.

Difference between formwork and shuttering

When to remove formwork for concrete slab?

Formwork removal time as per is 456

Also Read: Plinth Beam: Its Purpose, Importance & Protection in Building